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arXiv · 2311.03803

Non-Hermitian skin effect and nonreciprocity induced by dissipative couplings

Xinyao Huang·Yaohua Li·Guo-Feng Zhang·Yong-Chun Liu
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Abstract

We study the mechanism for realizing non-Hermitian skin effect (NHSE) via dissipative couplings, in which the left-right couplings have equal strengths but the phases do not satisfy the complex conjugation. Previous realizations of NHSE typically require unequal left-right couplings or on-site gain and loss. In this work we find that when combined with the multichannel interference provided by a periodic dissipative-coherent coupling structure, the dissipative couplings can lead to unequal left-right couplings, inducing NHSE. Moreover, we show that the non-Hermiticity induced by dissipative couplings can be fully transformed into nonreciprocity-type non-Hermiticity without bringing extra gain-loss-type non-Hermiticity. Thus, this mechanism enables unidirectional energy transmission without introducing additional insertion loss. Our work opens a new avenue for the study of non-Hermitian topological effects and the design of directional optical networks.

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Xinyao Huang, Yaohua Li, Guo-Feng Zhang, Yong-Chun Liu. 2023-11-07. Non-Hermitian skin effect and nonreciprocity induced by dissipative couplings. https://arxiv.org/abs/2311.03803

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